Hent exchanger



June 23,1925. 1,542,978

K. K. WRIGHT I HEAT EXCHANGER Filed NOV. 17, 1922 Patented June 23,1925.

UNITED STATES PATENT OFFICE.

KIRK K. WRIGHT, or BUFFALO, new YORK, ASSIGNOR T 3. G. WRIGHT & 00., 0F

BUrn'iLo, NEW YORK.

HE! .T EXCHANGER.

Application filed November 17, 1922. Serial No. 601,601.

To all whom it may concern.

Be it known that I, KIRK K. WRIGHT, a citizen of the United States,residing at Buffalo, in the county of Erie and State 6 of New York, haveinvented a new and useful Improvement in Heat Exchangers, of which thefollowing is a specification.

This invention relates to heat exchangers for liquids of the kind inwhich the liquid to be cooled or heated passes over a series ofhorizontally arranged, superimposed tubes through which a temperaturechanging medium is circulated.

The invention is primarily intended to be used as a cooler for liquidsand particularly for milk or other liquids which necessitate a. thoroughcleansing of the portions of the apparatus with which the liquid comesinto contact, but it is not intended to limit the invention to use inconnection with coolers for such liquids, since the apparatus may beused advantageously in connection with either the heating orthecoolingof'any liquid.

In coolers of this kind, it is necessary in order to have the cooleroperate at its full efliciency, to provide means for ensuring thatsubstantially equal quantities of liquid flow down on opposite sides ofthe cooler and for this purpose in coolers as heretofore constnucted, ithas been found necessary to place inserts between' the adjacentsuperimposed horizontal tubes or pipes in such a way as to prevent theliquid from flowing from one side of the vertical series of pipes to theother side thereof, and various means have been devised for thispurpose, all of which, however, add greatly to the expense of the cooleror are otherwise objectionable.

The objects of this invention are to provide a cooler consisting of aseries of substantiallyhorizontal, superimposed pipes which are arrangedin such close proximity to each other as to permit the adjacent tubes tobe connected by means of solder; also to provide improved means forconnecting the tubes to the headers arranged at the sides thereof so asto permit the tubes to be placed substantially into contact with eachother without weakening the construction of the headers; and also toimprove the construction of cooling devices of this kind in otherrespects hereinafter specified.

In the accompanying drawings:

Fig. l is a. side elevation, partly in section of a milk coolerembodying the invention.

Fig. 2 is a fragmentary longitudinal central sectional elevationthereof.

F 1g. 3 is a fragmentary perspective View thereof.

Fig. 4 is a fragmentary elevation of one of the headers of the cooler,showing the niinating in the headers, the headers being preferablyprovided with a plurality of partition walls a, which cause the coolingmedium to flow from one pipe to an acent pipe. a and a? representrespectively the inlet and discharge pipes for the cooling medium. Crepresents the usual supply or distributing trough arranged above thecooler and provided in its bottom with two series of discharge holes ororifices b and b' through which the milk or liquid to be cooled orheated may be discharged to opposite sides of theup r pipe of thecooler. These discharge ori ices are so arranged with reference to theupper pipe that approximately the same amount of liquid passes to eachside of the cooler, so that both sides of the apparatus will be utilizedfor cooling the liquid. I

In order'to arrange the pipes B so that each pipe either touches theadjacent pipe or pipes or is arranged in close proximity thereto, itwould be necessary to bore holes in the headers for the ends of thepipes which would be either tangent or else in such close proximity toeach other as to leave only a very thin portion of metal betweenadjacent holes. It is, however, impossible to accurately drill holes insuch a manner that they will be tangent, since the cutting tool willtend to move during its cutting operation toward the adjacent hole inthe header. For the same reason it is necessary to leave sufiicientthicknem of metal between holes so that the metal between adjacent holeswill be of sutlicient strength to prevent deformation by a cutting toolwhen operating in close proximity to the edge of a hole. For thesereasons it has heretofore been found impractical to machine the headersso as to bringthe adjacent tubes into contact or into close proximity toeach other.

In order to overcome this difficulty, I have provided a constructionwhereby the holes in the headers may be drilled at sufficient distancesapart so that the metal between adjacent holes will be of sufficientthickness and strength to make accurate machining of the headerspractical. This is done by securing short sleeves or inner tubes D intothe ends of each cooling tube B, each of these insert tubes D extendingbeyond the end of the tube B and being adapted to extendinto a hole (Zin the header. Any suitable means may be employed for securing theinsert tubes or sleeves in place in the outer or cooling tubes, theinsert tubes being generally soldered into the outer tubes.

Consequently, the holes in the header may be drilled far enough apart sothat the metal between holes is twice the thickness of the metal in thetubes B, which is sufficient to make accurate machining easily possible.Consequently, when ehe cooling tubes B with the insert tubes D thereinare assembled into the headers. the insert tubes D will be spaced apart,but the outer tubes B will be tangent, or in close proximity to eachother. The insert tubes extend slightly beyond the ends of the outertubes, and the holes (Z in the headers are preferably bored ofSll'lllClGlll) depth so that the ends of the holes will form stopshoulders (1 against which the ends of the insert tubes engage tofacilitate the correct assembling of the cooler.

After the tubes and headers have been assembled, the tubes arepreferably connected or secured together by means of bonding material,such as solder or other molten metal, in such a manner that the bondingmaterial will fill the spaces or angular recesses between adjacenttubes. These angular'recesses cause the molten metal or other materialto be readily retained therein, so that-the adjacent portions of thetubes are connected by strips E of solder or other metal, see' Fig. 8,of wedge shaped cross section. This closes the angular or wedge shapedrecesses and thus positively prevents the liquid which is being heatedor cooled from passing from one side of the cooler to the other and alsogreatly facilitates the cleaning of the heat exchanger in that thesolder or other material E fills those portions of the spaces betweenadjacent tubes which are most ditlicult to clean and which most readilycollect dirt or other foreign matter. The solder or other material E atthe same time forms a connection between the several tubes which greatlystrengthens the apparatus.

A heat exchanger constructed as described, has the advantages overapparatus of this I kind heretofore built in that the constructiondescribed canbe produced" at a lower cost and at the same time possessesgreater strength than similar apparatus heretofore constructed.

I claim as my invention 1. In a heat exchanger. the combination of aplurality of tubes of s hsta uniform diameter, headers with which saidtubes communicate and provided with a series of holes of smallerdiameter than the outside diameter of said tubes each hole being spacedapart from adjacent holes, insert sleeves projecting into the ends ofsaid tubes and into said holes in the headers, said sleeves being ofsubstantially uniform diameter throughout their lengths whereby saidtubes may be placed in close proximity or in contact,-a'nd bondingmaterial forming a connection between said tubes and filling the spacesbetween adjacent tubes.

2. In a heat exchanger, the combination of a plurality of tubes, headerswith which said tubes communicate and provided with a series of holes ofsmaller diameter than the outside diameter of said tubes, insert membersarranged within said tubes and extending into said holes and serving tospace said tubes in close proximity to each other and forming a rigidconnection between said headers and said tubes, and a bonding connectionbetween adjacent tubes which fills the spaces between tubes and forms aconnection between tubes.

3. In a heat exchanger, the combination of a plurality of tubes, headerswith which said tubes communicate and having holes of smaller diameterthan the outside diameter of said tubes, insert members fitting closelyinto said tubes and into said holes and serving to space said tubes inclose proximity to each other, and to form rigid connection between saidheaders and said tubes, stop portions in said holes with which saidinsert members are adapted to engage to limit the extent to which saidinsert members may enter said holes, and a metallic bonding connectionbetween adjacent tubes which fills the sharp angled recesses betweenadjacent tubes.

KIRK K. WRIGHT.

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